# BMI=weight/height**2
# input的返回值是字符串
weight = float(input("请输入你的体重(kg):"))
height = float(input("请输入你的身高(m):"))
BMI = weight / (height ** 2)
# print里面+两边只能是字符串
print("你的BMI值为" + str(BMI))

# python的if语句支持左右连续判断
if 0 < BMI <= 18.5:
    print("偏瘦")
elif BMI <= 25:
    print("正常")
elif BMI <= 30:
    print("偏胖")
else:
    print("肥胖")
